Portion of an article of footwear



FIG. 1 is a perspective view of a portion of an article of footwear showing my new design;

FIG. 2 is a bottom plan view of the article of FIG. 1.

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a front elevational view of the article of FIG. 1; and,

FIG. 6 is a rear elevational view of the article of FIG. 1.

The broken lines shown in FIGS. 1-6 immediately adjacent the shaded areas represent the bounds of the claimed design while all other broken lines are directed to environment and are for illustrative purposes only; the broken lines form no part of the claimed design. 

The ornamental design for a portion of an article of footwear, as shown and described. 